1. Field of the Invention
The present invention relates to vehicles suitable for traveling over rough terrain.
2. Description of the Related Art
Vehicles suitable for traveling over rough terrain are conventionally known. Among such vehicles are an all-terrain vehicle (hereinafter referred to as an “ATV”) and a recreational off-highway vehicle (hereinafter referred to as an “ROV”). Although some ATVs and ROVs include continuously variable transmissions (CVTs), it is desirable to develop ATVs and ROVs including traditional transmissions with the aim of further improving durability, for example.
For example, U.S. Pat. No. 6,443,275 and U.S. Pat. No. 6,257,081 each discloses an ATV including an automated manual transmission (AMT). Such an ATV includes an engine integral with a transmission case housing the transmission. A shift actuator and a clutch actuator are directly attached to the engine integral with the transmission case. U.S. Pat. No. 5,967,252 discloses a vehicle including an engine integral with a mechanical transmission, and a shift actuator fixed to a forward portion of a body frame so as to aid in shifting gears with a shift pedal. This vehicle allows the shift actuator to operate a link connected with the shift pedal, thus performing a gear shifting function.
Unfortunately, a vehicle such as an ATV or ROV requires that an engine and a transmission be disposed in a limited space inward of a body frame. In particular, the space in which to dispose a large engine integral with a transmission is severely limited, which significantly reduces layout flexibility. In the ATV disclosed in each of U.S. Pat. No. 6,443,275 and U.S. Pat. No. 6,257,081, the engine and the transmission case are integral with each other, and the shift actuator, for example, is fixed to the engine. This causes the engine to further increase in size. Installing such a large engine requires a considerably large space, thus reducing layout flexibility. In the vehicle disclosed in U.S. Pat. No. 5,967,252, the shift actuator and the transmission are spaced apart from each other, so that a component, such as a cable, for use in operating the transmission increases in length. Consequently, a resulting transmission system increases in size.